The present invention relates to utility vaults and the hatches provided for access thereto. In particular, the invention provides a motorized operator for opening and closing the vault hatch.
Hatches for utility vaults are usually manually opened and closed by service personnel. It has been brought to the attention of the inventor that to obtain access to such vaults, service personnel must unlock and manually open the hatch. After opening, the service person secures a detent provided to hold the hatch open, and enters the vault shroud to descend a service ladder to the underground vault interior. While still standing on the ladder, and possibly holding tools, service equipment and spare parts, the service person must release the detent, and close the hatch as he or she descends the ladder to the vault interior. This operation can be awkward and prone to accidental falls and injury.
Automatic swing door operators, as disclosed in U.S. Pat. No. 4,333,270 to John C. Catlett, are commonly used for vertically-mounted, conventional swing doors. Such operators are mounted either within the door header or on the one side of the door frame above the door, outside of the door opening. Since vault hatches have neither a door header nor a surrounding frame, door openers cannot be conventionally mounted thereto. Further, the motivation for providing automatic door operation in most instances, i.e., convenience of customers and frequent door use, are absent in the instance of a vault hatch. Finally, the vault hatch environment provides special problems associated with power or equipment failure not found in the conventional door application.
It is therefore an object of the present invention to provide improved safety in connection with service personnel entering or leaving a utility vault, by providing a motorized vault hatch operating system.